TitleAbstractYear(sorted descending)
polyploidy induced by x rays during the generation cycle of synchronized chinese hamster cells. anl-7635. 19695310801
cytological studies on cysteamine protected chinese hamster cells in vitro. anl-7635. 19695310800
ultraviolet light-induced division delay in synchronized chinese hamster cells. anl-7635. 19695310798
the effect of x rays on the uptake of 3h-leucine in synchronized chinese hamster cells. anl-7635. 19695310797
cycloheximide- and radiation-induced division delay in synchronized chinese hamster cells. anl-7635. 19695310796
sensitization of chinese hamster cells to x-rays by n-ethylmaleimide. anl-7635. 19695310795
recovery from sublethal damage induced by x irradiation in cysteamine protected chinese hamster cells. anl-7635. 19695310792
the cell cycle distribution of chinese hamster cells in stationary phase cultures. anl-7635. 19695310791
genetics of somatic mammalian cells. x. complementation analysis of glycine-requiring mutants.complementation analysis at the single gene level has been carried out on 13 different, recessive, glycine-requiring mutants produced by action of mutagenic agents on the cho-k1 chinese hamster cell. the mutants form four different complementation classes indicating that at least four separate genes can produce a growth requirement for glycine. the four classes of mutants can be distinguished biochemically as well as genetically. existence of these four mutant classes appears to explain the prep ...19695271752
[study of sensitivity of inhibitors of rna and protein synthesis during the individual stages of the mitotic cycle in cell cultures of the chinese hamster]. 19694246154
synchronized mammalian cell cultures. 3. variation of ribonucleotide reductase activity during the replication cycle of chinese hamster fibroblasts. 19695408612
radiosensitivity of mammalian cells. 3. effect of suboptimal growth temperatures on recovery from radiation-induced division delay.we investigated the effect of suboptimal growth temperatures on recovery from radiation-induced division delay in chinese hamster cells. it was found that no recovery occurred during the time that either log-phase or synchronized populations were incubated at 4 degrees c and that injury sustained at low dose rates was cumulative over a period of 6.2 hr at low temperature. postirradiation conditions influencing recovery from the induced division delay period are different from those affecting sur ...19695389451
temporal order in mammalian cells. i. the periodic synthesis of lactate dehydrogenase in the cell cycle.chinese hamster cells were synchronized by the colcemid-selection system. in cells with a division cycle time of 11.5-12 hr, the activity of the enzyme lactate dehydrogenase (ldh) underwent marked oscillations with a 3.5-hr period. precipitation of labeled ldh enzyme with specific antibody indicated that the enzyme activity changes were the result of intermittent enzyme synthesis and relatively constant degradation. inhibition of normal dna replication with 4 mm of thymidine, while reducing the ...19695344146
metabolism and toxicity of 241am in the chinese hamster. lf-41. 19695310179
60co-induced metaphase chromosome aberrations in chinese hamster liver cells. lf-41. 19695310175
effects of hypertonic sucrose on the radiosensitivity of chinese hamster fibroblasts. 19695345342
x-ray induction of chromatid exchanges in mitotic and g1 chinese hamster cells pretreated with colcemid. 19695810929
sensitivity of synchronized chinese hamster cells to ultraviolet light.the age response for lethality of chinese hamster cells to ultraviolet light shows that they are resistant in g(1), sensitive as they move into and through the s phase and resistant again in g(2) and mitosis. survival curves determined at different times in the cycle reveal that mitotic cells are the most resistant fraction, much more resistant than s cells, and more resistant than either g(1) or g(2) cells. the extent to which the age response is ilfluenced by nucleic acid and protein synthesis ...19695807224
x-rays and nitrogen mustard: independent action in chinese hamster cells.we have studied the combined effects of x-irradiation and nitrogen mustard treatment on the colony-forming ability of chinese hamster cells. in contrast to x-irradiation, nitrogen mustard acting by itself yields an exponential dose-effect relationship. moreover, whether delivered in immediate sequence or after varying intervals, nitrogen mustard treatment does not affect radiation survival and vice versa. these results, plus the lack of any indication of the repair of sublethal nitrogen mustard ...19695807220
cell killing by actinomycin d in relation to the growth cycle of chinese hamster cells.using chinese hamster cells in culture, we have measured the effectiveness of actinomycin d to suppress division as a function of the position, or age, of a cell in its growth cycle. cells were first exposed to millimolar concentrations of hydroxyurea in order to produce a synchronized population just before the onset of dna synthesis. thereafter, the survival response after 30 min exposures to actinomycin d was measured. cells become resistant as they enter the s phase and then sensitive again ...19695792326
modesl of growth in mammalian cells.the increase of cell volume as a function of time was studied throughout the generation cycle in synchronous cultures of chinese hamster cells using a coulter aperture and a multichannel analyzer calibrated against known cell volumes. the experimental results were compared to a mathematical model of cell volume increase which considered the effect of the distribution of individual cell generation times on the progress of the population. several modes of volume increase, including linear and expo ...19694898382
the effect of excess methionine on the pancreas. a light and electron microscopic study in the chinese hamster with particular reference to degenerative changes. 19694896281
single strand interruptions in dna and the effects of caffeine in chinese hamster cells irradiated with ultraviolet light. 19695816421
rna synthesis in chinese hamster cells. ii. increase in rate of rna synthesis during g1.cultures of mitotic chinese hamster cells, prepared by mechanical selection, were pulse-labeled with methionine-methyl-(14)c or with uridine-(3)h at different stages in the life cycle. the rate of (14)c incorporation into 18s rna was measured, as was the rate of uridine-(3)h incorporation into total rna for both monolayer and suspension cultures. the rate of incorporation increased continuously throughout interphase in a fashion inconsistent with a gene-dosage effect upon rna synthesis.19695795885
fertilization of chinese hamster eggs in vitro. 19695793469
protection by cysteamine against lethal x-ray damage during the cell cycle of chinese hamster cells. 19695789038
mammalian cell genetics. i. selection and characterization of mutations auxotrophic for l-glutamine or resistant to 8-azaguanine in chinese hamster cells in vitro. 19695392645
the effect of histones, poly-l-lysine and dna on the mitotic activity of chinese hamster fibroblasts. 19695388934
isolation and characterization of thymidine transport mutants of chinese hamster cells. 19694182358
post-irradiation properties of cultured chinese hamster cells exposed to ultraviolet light. 19695771800
vinblastine-induced chromosomal alterations in cultured chinese hamster cells. 19695360881
complementation analysis on virus-fused chinese hamster cells with nutritional markers.cell fusion experiments have been carried out with chinese hamster cell mutants with different nutritional growth requirements. conditions have been devised in which approximately 1 to 2 percent of the cell population remaining after fusion are fused, hybrid cells. the all-or-none nature of the genetic markers employed and the extremely low reversion rates insure that no contamination of the hybrid population with parental forms occurs. hybrids between glycine- and hypoxanthine-requiring mutants ...19695813351
effect of mannitol mustard (nsc-9698) on nuclear dna content and birefringence of hela and chinese hamster cells. 19695799416
segregation of chromosomal dna in chinese hamster fibroblasts in vitro. 19695780787
observations on nuclear rotation and oscillation in chinese hamster germinal cells in vitro. 19694888994
low molecular weight methylated ribonucleic acid species from chinese hamster ovary cells. i. isolation and characterization. 19695781009
a correlation between division delay and loss of colony-forming ability in chinese hamster cells irradiated in vitro. 19695305083
[particular nutritive need of chinese hamster cells transformed in vitro by adenovirus 12]. 19694975884
chromosomal nondisjunction: the action of colcemid on chinese hamster cells in vitro. 19695798031
the oxygen effect and x-ray sensitivity in synchronously dividing cultures of chinese hamster cells. 19695762918
chromosome breakage induced in vivo by a carcinogenic hydrocarbon in bone marrow cells of the chinese hamster. 19695399201
autoradiographic study on the synthesis of nuclear proteins. vi. the data on the turnover rate of nuclear proteins and formation of the protein component in chromosomes of chinese hamster cells cultured in vitro. 19695392209
late-replicating y chromosome in spermatogonia of the chinese hamster (cricetulus griseus). 19695381336
morphologic effects of ethionine on the pancreas of the chinese hamster. a light and electron microscopic study of degenerative changes. 19695350754
chronology of chromosome reduplication in chinese hamster cells incubated at low temperature. 19695345641
late-replicating y chromosome in spermatogonia of the chinese hamster (cricetulus griseus). 19695344998
progession of viable and non-viable synchronized chinese hamster cells into the s phase after x-irradiation in mitosis or the s phase. 19695308936
dna repair in chinese hamster cells of different sensitivities to ultra-violet light. 19695308017
sites of nucleolus production in cultured chinese hamster cells.chinese hamster cell strains in the early passages in culture display wide variation in number of nucleolus-like bodies per cell, though such strains are characteristically euploid. a variety of criteria indicate that the nucleolus-like bodies are true nucleoli. their azure b- and fast green-staining properties indicate the presence of rna and protein; they have typical nucleolar fine structure, including both fibrous and granular components; radioautography reveals that their patterns of uptake ...19694177660
comparative effects of cortisone and acth on golden and chinese hamsters infected with trichinella spiralis. 19684319345
[heterotransplantation of zajdela hepatoma of the rat to golden hamsters, mice, and chinese hamsters]. 19684182272
clonal analysis of embryonic chinese hamster cells transformed by schmidt-ruppin rsv in vitro. 19684297600
transfer of defective rous sarcoma virus genome from chinese hamster embryonic cells to chicken cells. 19684298067
chromosome breakage induced by a carcinogenic hydrocarbon in chinese hamster cells and human leukocytes in vitro. 19684299249
chromosome pulverization in chinese hamster cells induced by sendai virus. 19684301272
effect of immunosuppressive drugs (6-mercaptopurine and methotrexate) on resistance of chinese hamsters to the tissue phase of trichinella spiralis. 19685698690
the intracellular distribution of basic proteins in the chinese hamster ovary cell. 19685761384
radiosensitivity of mammalian cells. ii. radiation effects on macromolecular synthesis.radiation effects on macromolecular synthesis essential for the chinese hamster cell to traverse the life cycle and to divide have been investigated. life-cycle analysis techniques employing inhibitors of macromolecular synthesis were used in determining the kinetics of cell growth for specific segments of the population following spontaneous recovery from radiation-induced division delay. the results indicated that recovery does not occur in the absence of functional protein synthesis. under co ...19685753224
radiosensivity of mammalian cells. i. timing and dose-dependence of radiation-induced division delay.the time of onset and duration of division delay induced by exposure to 250-kvp x-irradiation have been measured in several mammalian cell lines grown in suspension culture. unique times of action (i.e. interval from irradiation to cessation of division) late in g(2) are characteristic for hela, l-5178y, and chinese hamster cells, and the time of action is independent of dose over the range 25-800 rads. the duration of delay was directly proportional to dose; all irradiated cells divided at leas ...19685753223
the effect of cysteamine on chromosomal aberrations and division delay in chinese hamster cells. anl-7535. 19685307188
sensitivity of synchronized chinese hamster cells to ultraviolet light. anl-7535. 19685307187
the effect of ultraviolet irradiation on the progression of chinese hamster cells through the cell cycle. anl-7535. 19685307186
protection by cysteamine against x-ray damage during the cell cycle of chinese hamster cells. anl-7535. 19685307185
mating systems for chinese hamster production. anl-7535. 19685307180
computer analysis of chromosomes of the chinese hamster. anl-7535. 19685306862
mammalian cell genetics. ii. chemical induction of specific locus mutations in chinese hamster cells in vitro. 19685249812
determining the repair rate for radiation-induced chromatid deletions during the first 24 hours after irradiation.the number of chromatid plus isochromatid deletions present in the testes and bone marrow of the chinese hamster was measured as a function of time following acute exposure to cobalt-60 gamma irradiation. the number of breaks remaining scorable at any time after irradiation exposure could be represented by a simple exponential equation (n = noe-kt). the values of no and k, calculated after 100 roentgens of cobalt-60 gamma irradiation, were 1.15 breaks/cell and 0.16/hour, respectively, for the te ...196817387938
the interaction between gamma and ultraviolet irradiations for survival in a chinese hamster cell line. 19685696537
comparison of ultraviolet and x-ray effects in cultured chinese hamster cells. 19685696536
[time of synthesis and rate of renewal of chromosome proteins in cells of regrafted fibroblast cultures of the chinese hamster]. 19685745596
x-ray sensitivity of synchronized chinese hamster cells irradiated during hypoxia.synchronized chinese hamster cells were irradiated in air and in nitrogen at various points in the cell cycle. the irradiations were carried out after flushing with air or nitrogen with the medium removed from the mono-layer of cells. under these conditions the dose-modifying factor, or oxygen enhancement ratio, was between 2.0 and 2.3 for survival in asynchronous cells. the variation in x-ray sensitivity evident as the cell progresses through its cycle was not differentially affected by its sta ...196817387925
rapidly-labeled nuclear rna in chinese hamster testis. 19685749522
fertilization and early development in the chinese hamster, cricetulus griseus. 19685726140
cytogenesis in primary cell cultures of chinese hamster kidneys. 19685693647
sucrose-induced vacuolation in living chinese hamster fibroblasts. 19684879077
breakdown and assembly of polyribosomes in synchronized chinese hamster cells.polyribosomes were absent in metaphase chinese hamster cells and were reassembled after mitosis. this assembly correlated temporally with formation of nuclear membrane and decondensation of chromatin, accounted for a threefold increased rate of protein synthesis, and occurred independently of de novo rna synthesis, that is, it utilized preexisting messenger rna.19685663806
cytogenetic effects of strontium-90 on the bone marrow of the chinese hamster. 19685667080
cytological effects on chinese hamster cells of synchronizing concentrations of hydroxyurea. 19685678454
genetics of somatic mammalian cells, vii. induction and isolation of nutritional mutants in chinese hamster cells. 19685244736
responses of cultured chinese hamster cells to ultraviolet light of different wavelengths. 19684874350
comparison of repair of sublethal damage in cultured chinese hamster cells exposed to sulfur mustard and x-rays. 19685661065
differences in survival variations during the growth cycle of cultured chinese hamster cells treated with sulfur mustard and x-rays. 19685658444
comparison of survival kinetics and modifications of lethal damage in cultured chinese hamster cells exposed to sulfur mustard and x-rays. 19685658443
incorporation of 14c from [2-14c]methionine into 18 s but not 28 s rna of chinese hamster cells. 19685646651
persistence of chromosomal aberrations in chinese hamster thyroid following administration of 131-i. 19685638630
rna synthesis in chinese hamster cells. i. differential synthetic rate for ribosomal rna in early and late interphase.the incorporation of methionine-methyl-(14)c into 18s ribosomal rna of cultured chinese hamster ovary cells in early and late interphase has been determined by zone-sedimentation analysis of phenol-extracted rna preparations. synchronized cell cultures were prepared for these studies by thymidine treatment and by mechanical selection of mitotic cells. the specific activity of 18s rna labeled in late interphase was found to be 1.1-1.2 times that of 18s rna labeled in early interphase. upon correc ...19685645548
separation of isolated chinese hamster metaphase chromosomes into three size-groups. 19684230571
failure of chinese hamster cells to repair sub-lethal damage when x-irradiated in the plateau phase of growth. 19685641124
cyclic changes in enzyme activity in synchronized mammalian cell cultures.activity of the enzymes glucose-6-phosphate dehydrogenase and lactate dehydrogenase increases intermittently in synchronized cultures of chinese hamster cells. during g(1) phase (3 hours after mitosis), midway through s phase (7 hours after mitosis) and again in late s phase (10 hours after mitosis), rapid increases in activity were observed and correlated with a net increase in cell size and total protein. the evidence suggests that this is a general phenomenon which affects a whole population ...19685716136
chinese hamster cell monolayer cultures. ii. x-ray sensitivity and sensitization by 5-bromodeoxycytidine in the exponential and plateau periods of growth. 19685761386
chinese hamster cell monolayer cultures. i. changes in cell dynamics and modifications of the cell cycle with the period of growth. 19685761385
the combined effect of hydroxyurea and x-rays on chinese hamster cells in vitro. 19685641513
cysteamine: differential x-ray protective effect on chinese hamster cells during the cell cycle.cysteamine present during x-irradiation protects synchronized chinese hamster cells in culture against lethal damage at all stages of the cell cycle. the effect is greatest for cells irradiated at sensitive stages such as g(1) and least for resistant cells; for example, late s (dose-modifying factors 4.2 and 2.7, respectively). the effect of 50 millimolar cysteamine is to render almost invariant the normally variant x-ray age response for lethality. this suggests that there are two components of ...19685634666
growth-promoting effect of lysolecithin on chinese hamster cells in vitro. 19685639135
synchronization of chinese hamster ovary cells in a tissue culture pilot plant. la-3848-ms. 19685302794
characterization of chinese hamster ovary histone fractions. la-3848-ms. 19685302792
[action of cysteamine on the chromosomes of chinese hamster fibroblasts in culture]. 19684967251
[effects of decrease of temperature on the mitotic activity of chinese hamster cultures]. 19685761258
asynchrony of dna replication and mitotic spiralization along heterochromatic portions of chinese hamster chromosomes. 19685662571
chromosomal changes in the chinese hamster thyroid following x-irradiation in vivo. 19685303350
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